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Drink Mixer (Audio Mixer)

The Drink Mixer is a 6-8 Channel Audio Mixer with a peripheral interface operated by the Tin Can Tools Hammer. This was a Senior Design Project presented for Purdue University's Senior Design Class ECE 477. In order to pass this class at least 3 of 5 project success criteria must be completed.

Project Success Criteria:

1. An ability to mix and adjust levels of 6-8 Channels of Audio

2. An ability to change individual equalizer settings for each channel.

3. An ability to display settings/ channel information on an LCD Display.

4. An ability to save and load scene settings (moving faders)

5. An ability to display the amplitude of an audio output signal.

Of the above project success criteria, currently 2,3, and 4 are completed with the help of the Hammer ARM920T Chip.

More information and pictures will be added to this later but for now a link to the Purdue University Senior Design Project Page for this project can be found below.

Hardware

The Hammer is not capable of processing audio at rates necessary for this project with all of the floating point calculations involved. As a result several processors were used

1 - ADSP-21262 SHARC DSP
10 - AVR ATMEGA32A

The ATMEGA32A were used as peripheral processors that kept track of motorized faders as well as Rotary Pulse Generators (RPGS) and LED Bar graphs. These processors were all placed on an i2c bus and monitored and updated several times / second by the Hammer S3C2410A ARM920T Processor.

The information acquired by the Hammer from the various peripherals as well as the user interface are then sent to a SHARC ADSP-21262 over an SPI bus. This information is processed and audio levels are adjusted accordingly. (Currently the audio portion of the project is incomplete as too much crosstalk is occurring on the A/D Data line).

Pictures

This is a picture of the hammer running on the main board.
This is an inside view of the DrinkMixer (Audio Mixer Board). It's getting to be quite a lot of wires. This is mainly due to our PCB restriction of a maximum of 60 square inches per PCB.

Useful Resources

Throughout the development cycle of this project many resources were utilized from this site as well as improved upon and/or updated.